Add Managed (generic RAII type).

1 files changed, 16 insertions, 0 deletions

diff --git a/c/util.h b/c/util.h
index 7ca8bfe..c08050d 100644
--- a/c/util.h
+++ b/c/util.h
@@ -23,6 +23,22 @@ inline int Cmp(const int a, const int b)
 	return -1;
 }
 
+template <typename T, auto F, typename U, auto E = 0>
+struct Managed
+{
+	T obj;
+	Managed(T obj) : obj(obj)
+	{
+		if (obj == reinterpret_cast<T>(E))
+			throw U();
+	}
+	~Managed() { F(obj); }
+	operator T() { return obj; }
+	auto& operator *() { return *obj; }
+	auto& operator ->() { return obj; }
+	auto& operator [](size_t i) { return obj[i]; }
+};
+
 /* Buf is a span-like structure of a buffer and its size. */
 template <typename T>
 struct Buf